Original Post

Background:
Received a bad Virtual Boy, looked like it was stored in a puddle, one eye did not work at all, corrosion everywhere, the mechanical parts did not work at all, and some PCB’s suffered issues.
Both Eye LEDs worked on the single working side of the VB Main board.
I ended up consolizing this unit in a 3d printed case, with the servo emulator.

Issues Seen:
– Video artifacts / garbage
– Sound low frequency hum
– No video artifacts aparent on the lenses direct to the virtual boy hardware. (Have not checked while plugged into the VirutalTap)

Steps Taken:
– Reflowed and double/triple checked the Virtualtap for any solder bridges
– Cleaned/Reflowed main Virtual Boy board (Actually got the 2nd Eye working after the rework of the vb mainboard)
– Checked Virtualboy Capacitors in LCR Meter, seem good.
– Added / Moved any Additional Grounds (No changes seen)

Videos Here:
Video Interference – https://www.youtube.com/watch?v=ElvG66yxGxM
Audio Interference – https://www.youtube.com/watch?v=ODDaRXLCHTo

Any Ideas? (Other than this VB is toast, im trying to source another to test it out)

1 Reply

Just going to update this.

It appears that the SRAM Chip I was using, is not 100% compatible with the original from Furrteks BOM.
Nothing is wrong with the VirtualTap or install, just the wrong memory chip.

I was using a Renesas 71V016SA12PHG, but we need to use the ISSI IS61WV6416BLL-12TLI as it works perfectly.

Datasheets of working SRAM:
BOM SRAM IC – IS61WV6416BLL-12TLI
http://www.issi.com/WW/pdf/61-64WV6416BLL.pdf
ISSI Recommends their new replacement (not tested) – IS61WV6416DBLL
http://www.issi.com/WW/pdf/61-64WV6416DAxx-DBxx.pdf

Chip that didnt work (I did update the pin assignments to account for the address lines numbered differently)
https://www.idt.com/us/en/document/dst/71v016sa-datasheet

  • This reply was modified 1 week, 3 days ago by Alterac.

 

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